I put it now here:
http://home.chiemgau-net.de/ausserstorfer/Computer/Kurs.pdf (27 kB)
You'll find an update now here:
http://home.chiemgau-net.de/ausserstorfer/Temp/2025-11-02/2025-08-31_PHB.pdf
(around 4 megabytes now).
In article <5c2cea6fccbavariasound@chiemgau-net.de>,
Alexander Ausserstorfer <bavariasound@chiemgau-net.de> wrote:
I discovered some interesting points. I will write about later here.
In article <5c75805cc6bavariasound@chiemgau-net.de>,
Alexander Ausserstorfer <bavariasound@chiemgau-net.de> wrote:
You'll find an update now here:
http://home.chiemgau-net.de/ausserstorfer/Temp/2025-11-02/2025-08-31_PHB.pdf
(around 4 megabytes now).
I have had a very quick look at your pdf, but I have not translated
it. However, I have noticed some possible confusion between the ! and
? indirection BASIC operators...
In article <5c75805cc6bavariasound@chiemgau-net.de>,
Alexander Ausserstorfer <bavariasound@chiemgau-net.de> wrote:
In article <5c2cea6fccbavariasound@chiemgau-net.de>,
Alexander Ausserstorfer <bavariasound@chiemgau-net.de> wrote:
I discovered some interesting points. I will write about later here.
What I don't understand ist that: Bruce Smith wrotes in his book, that
the command
MOV PC, R14
will stop your programme and jump back to RISC OS.
In machine code, it has the value &E1A0 E00F.
This is okey.
But when I use the Acorn Assembler (DDE) to translate this command (MOV
PC, R14) to machine code (&E1A0 E00F) the result is much bigger as 4
bytes!
And if I use the GCC to convert the command MOV PC, R14 to machine code,
the result is not a file type of Absolute but of ELF and it has a file
size of huge blowy shit! 784 bytes for just ONE command! I don't
understand that.
On 15 Nov, Alexander Ausserstorfer wrote in message
<5c7c29dce9bavariasound@chiemgau-net.de>:
And if I use the GCC to convert the command MOV PC, R14 to machine code, the result is not a file type of Absolute but of ELF and it has a file
size of huge blowy shit! 784 bytes for just ONE command! I don't
understand that.
Because an ELF file isn't just the code itself: it's a structured file that can contain more data. So somewhere in there will be the 4 bytes of the MOV command, plus a header to tell the ELF loader where in memory to put that command when it loads the file. And other infrastructure needed to allow the file to do things like initialise separate blocks of memory, or load other chunks of assembled commands, linkable blocks like libraries, and so on.
We moved on from doing *Save and *Load many years ago, because it's not that flexible and forces too many assumptions about the file contents to be made.
See https://en.wikipedia.org/wiki/Executable_and_Linkable_Format for
details.
Excuse me. I come from the Commodore 64 and do only know something about
the POKE and PEEK commands.
I don't understand the ! and ? commands. I found some PDFs online and
wonder because its about BBC BASIC but not for the Acorn Archimedes but
for a Z80 called Sinclair Spectrum and another for a Z88 system. So BBC
BASIC doesn't belong to RISC OS only?
? belongs to a byte ! belongs to a word.
With !(&9000) you can write into memory. But with the same command you
can read it!
I never have seen that before.
On 15 Nov, Alexander Ausserstorfer wrote in message
<5c7c29dce9bavariasound@chiemgau-net.de>:
And if I use the GCC to convert the command MOV PC, R14 to machine
code, the result is not a file type of Absolute but of ELF and it has
a file size of huge blowy shit! 784 bytes for just ONE command! I
don't understand that.
Because an ELF file isn't just the code itself: it's a structured file
that can contain more data. So somewhere in there will be the 4 bytes
of the MOV command, plus a header to tell the ELF loader where in
memory to put that command when it loads the file. And other
infrastructure needed to allow the file to do things like initialise
separate blocks of memory, or load other chunks of assembled commands, linkable blocks like libraries, and so on.
We moved on from doing *Save and *Load many years ago, because it's
not that flexible and forces too many assumptions about the file
contents to be made.
So
[OPT pass%
FNmessage("Harriet")
MOV R15, R14 ;exit routine
]
will generate a scrap of code that simply prints the string "Harriet".
However, you can do this much easier. Just write the hex
values
01 00 00 EF 48 61 72 72 69 65 74 00 0E F0 A0 E1
In article <050c4e7c5c.harriet@bazleyfamily.co.uk>,
Harriet Bazley <harriet@bazleyfamily.co.uk> wrote:
[part snipped]
So
[OPT pass%
FNmessage("Harriet")
MOV R15, R14 ;exit routine
]
will generate a scrap of code that simply prints the string "Harriet".
Thank you! However, you can do this much easier. Just write the hex
values
01 00 00 EF 48 61 72 72 69 65 74 00 0E F0 A0 E1
into the memory and run it.
It shouldn't be added automatically by the Assembler because this is a bit
of spoon-feeding (the German word here would be 'Bevormundung', I don't
know the correct English expression). You are hide here something from the programmer.
This is not a good way to learn! He should be able to know what he's
doing!
Unix, ugh!
In article <5c87099f9bbavariasound@chiemgau-net.de>,
Alexander Ausserstorfer <bavariasound@chiemgau-net.de> wrote:
However, you can do this much easier. Just write the hex
values
01 00 00 EF 48 61 72 72 69 65 74 00 0E F0 A0 E1
That to my mind is MUCH harder, and would give you maintenance
nightmares, as it is impossible to read easily. The computer is MUCH
better translating plain text into hex and binary then we are.
I strongly suggest that is not the way to program these days.
It was bad enough 50 years ago, when that was the only option, but
certainly not now.
In article <5c87163b82News04@avisoft.f9.co.uk>,
Martin <News04@avisoft.f9.co.uk> wrote:
In article <5c87099f9bbavariasound@chiemgau-net.de>,
Alexander Ausserstorfer <bavariasound@chiemgau-net.de> wrote:
However, you can do this much easier. Just write the hex
values
01 00 00 EF 48 61 72 72 69 65 74 00 0E F0 A0 E1
That to my mind is MUCH harder, and would give you maintenance
nightmares, as it is impossible to read easily. The computer is
MUCH better translating plain text into hex and binary then we
are.
I strongly suggest that is not the way to program these days. It
was bad enough 50 years ago, when that was the only option, but
certainly not now.
I don't understand that. The values are much more clear to me.
Without I couldn't understand how computers are working.
In article <5c87099f9bbavariasound@chiemgau-net.de>,
Alexander Ausserstorfer <bavariasound@chiemgau-net.de> wrote:
However, you can do this much easier. Just write the hex
values
01 00 00 EF 48 61 72 72 69 65 74 00 0E F0 A0 E1
That to my mind is MUCH harder, and would give you maintenance
nightmares, as it is impossible to read easily. The computer is MUCH
better translating plain text into hex and binary then we are.
I strongly suggest that is not the way to program these days.
It was bad enough 50 years ago, when that was the only option, but
certainly not now.
Thank you! However, you can do this much easier. Just write the hex
values
01 00 00 EF 48 61 72 72 69 65 74 00 0E F0 A0 E1
into the memory and run it. It does the same as your example programme.
On 06/12/2025 15:57, Alexander Ausserstorfer wrote:
Thank you! However, you can do this much easier. Just write the
hex values
01 00 00 EF 48 61 72 72 69 65 74 00 0E F0 A0 E1
into the memory and run it. It does the same as your example
programme.
I'm surprised you haven't gone for the even easier option of
toggling it in on the front panel switches, like a real programmer.
On 06/12/2025 15:57, Alexander Ausserstorfer wrote:
Thank you! However, you can do this much easier. Just write the
hex values
01 00 00 EF 48 61 72 72 69 65 74 00 0E F0 A0 E1
into the memory and run it. It does the same as your example
programme.
I'm surprised you haven't gone for the even easier option of
toggling it in on the front panel switches, like a real programmer.
In article <5c87850775bavariasound@chiemgau-net.de>,
Alexander Ausserstorfer <bavariasound@chiemgau-net.de> wrote:
In article <5c87163b82News04@avisoft.f9.co.uk>,
Martin <News04@avisoft.f9.co.uk> wrote:
In article <5c87099f9bbavariasound@chiemgau-net.de>,
Alexander Ausserstorfer <bavariasound@chiemgau-net.de> wrote:
However, you can do this much easier. Just write the hex
values
01 00 00 EF 48 61 72 72 69 65 74 00 0E F0 A0 E1
That to my mind is MUCH harder, and would give you maintenance
nightmares, as it is impossible to read easily. The computer is
MUCH better translating plain text into hex and binary then we
are.
I strongly suggest that is not the way to program these days. It
was bad enough 50 years ago, when that was the only option, but
certainly not now.
I don't understand that. The values are much more clear to me.
Without I couldn't understand how computers are working.
Good luck in understanding it in a year ... or two ...or many more.
Hex code I would not even try, stopping and improvment or development.
As Steve said, we may have to agree to differ!
May it be. For me, machine code is much more easy to understand. Because
you don't need a compiler it means that there is nothing between you and
the machine.
Now stop wasting everyone's time with this nonsense.
In article <10ic84f$3on78$1@druck.eternal-september.org>,
druck <news@druck.org.uk> wrote:
Now stop wasting everyone's time with this nonsense.
Now, now... Alex didn't waste my time. Although I will never touch machine code, it was pretty amusing to read that someone is so familiar with it.
In article <5c8f6b2891Paul@sprie.nl>,
Paul Sprangers <Paul@sprie.nl> wrote:
In article <10ic84f$3on78$1@druck.eternal-september.org>,
druck <news@druck.org.uk> wrote:
Now stop wasting everyone's time with this nonsense.
Now, now... Alex didn't waste my time. Although I will never touch
machine code, it was pretty amusing to read that someone is so familiar
with it.
I just try to understand and to learn. How can I do or learn coding when
I even don't understand any of the machine code, means _both_ sides of a compiler (or assembler)? I don't know what the program (compiler) is
doing. I don't say you should do it always like that. But you should be
able to do it! Without this knowledge, you aren't good. When you compare
the code (source) before the compiler and behind the compiler (machine
code), you'll learn and uncover a lot!
A.
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